(1) Dragging links to the tab bar to open them in a new tab (2) Drag text to the tab bar to search the text in a new tab Some other users reported a change, but I never used this myself before, so I am not sure: OLD: You could drop the selection in the blank space between the + button (or the List All Tabs "v" button) and the system buttons. NEW: That area is not allowed for dropping. You need to drop either: * In between existing tabs * On or before the + button Firefox should show an insert icon between tabs/buttons letting you know it is safe to drop (otherwise, you may change the content of the tab you drop it on). Does this match how your Firefox works?